Conventional wind turbines include a rotor 16 having two or more blades centrally mounted to a hub, as shown in FIG. 1. A rotor shaft 10 extends from the hub along a rotor axis 13 and is supported by rotor bearings in a bearing housing 20 that located within the nacelle 11 of the wind turbine 12. The bearings allow the rotor 16 to rotate about the rotor axis 13 (also referred to herein as the y-axis) while preventing the rotor from rotating about an axis 15 that lies perpendicular and substantially vertical to the rotor axis (referred to herein as the “z” axis) or an axis 14 that lies perpendicular and horizontal to the rotor axis (referred to herein as the “x” axis). It is to be appreciated that the bearings also prevent the rotor shaft from moving in translation along any direction, other than potentially along the rotor axis 13 by a nominal amount.
In conventional wind turbines, the rotor bearings are mounted within a housing that includes a forward rotor bearing seat and a rearward rotor bearing seat. Generally speaking, the conventional design approach that has been taken has been to provide a very stiff housing construction to prevent any movement or flexure at the bearing seats, and thus within the bearings. The applicant has appreciated, however, that allowing some limited degree of flexibility in areas of the bearing housing may promote increased bearing life.